title: Factor VIII:C and VIII:CAg response in patients with haemophilia A and von Willebrand's disease after administration of different factor VIII concentrates or plasma.
abstract: Factor VIII procoagulant activity (VIII:C) and factor VIII procoagulant antigen (VIII:CAg) were studied in seven patients with haemophilia A after administration of three different factor VIII concentrates or plasma. The in vivo recovery of VIII:CAg was less than that of VIII:C and the disappearance rate of VIII:CAg was much higher either when concentrates or plasma were given. The half-life of VIII:C was thus about 12 h but of VIII:CAg only about 3 h or less. Six patients with von Willebrand's disease were studied after administration of AHF-Kabi. In contrast to haemophilia A the discrepancy between VIII:C and VIII:CAg disappearance rates was not present in von Willebrand's disease, since both VIII:C and VIII:CAg showed a typical progressive increase. We conclude that factor VIII:C given to haemophilia patients does not behave like native VIII:C, not even when fresh plasma is used. Patients with von Willebrand's disease are capable of forming a normal VIII:C when appropriately stimulated.
mesh_terms: D000328:Adult; D000941:Antigens / Q000032:analysis; D001760:Bleeding Time; D002648:Child; D003029:Coagulants / Q000032:analysis; D005169:Factor VIII / Q000032:analysis / Q000276:immunology / Q000627:therapeutic use*; D006207:Half-Life; D006467:Hemophilia A / Q000097:blood* / Q000628:therapy; D006801:Humans; D008297:Male; D014842:von Willebrand Diseases / Q000097:blood* / Q000628:therapy
chemical_list: D000941:Antigens; D003029:Coagulants; D005169:Factor VIII